Professional papers of Gerard Hendrik Matthes, a hydraulic engineer and member of the U.S. Geological Survey, include material about projects investigating the Potomac, Susquehanna, Mississippi, Atchafalaya, Tennessee, Missouri, California, Ohio, and other rivers worldwide. Matthes was concerned about water policy, water conservation, and the legal aspects of of river and flood control.

The collection includes clippings, pamphlets, notes, reports, maps, surveys, blueprints, traverse books, binders, printed materials, volumes, photographs, and lantern slides on these subjects as well as on dam design, canals, irrigation, river geology, revetments, spillways, hydraulic design, and national resources. Personal papers include Matthes' writings and notes on topics such as entomology and paleobotany, as well as biographical information, scrapbooks, diaries, and photographs. Photographs include collectable travel views from Matthes' 1901 trip to Sumatra.